PSAD consists of three lightweight system daemons, offering a collection of software tools for enhancing network security and intrusion detection.
Psad is designed to detect different types of backdoor programs, DDoS tools, and advanced port scans that can be easily used against a machine through nmap. Combining with fwsnort, psad is capable of detecting approximately 50% of Snort rules that inspect the application portion of IP packets. Additionally, it makes use of various packet header fields associated with TCP SYN packets to identify the remote operating system fingerprints (in a similar way to p0f).
Psad follows three main principles of good network security, accurately configured firewalls, the significant amount of intrusion detection data available through firewall logs, and suspicious traffic detection without blocking it. The solution has several helpful features that allow administrators to configure and customize it to their needs. The latest release of the software includes new features such as ENABLE_AUTO_IDS_REGEX and AUTO_BLOCK_REGEX to allow filtering on logging prefixes, code to save DShield email to a file, added IPTABLES_PREREQ_CHECK to control the frequency of Netfilter checks, added IGNORE_LOG_PREFIXES to entirely ignore certain log prefixes, and so on.
Overall, psad is a highly effective and efficient software solution for detecting port scans and other suspicious traffic. Its flexibility and extensive features make it a valuable tool for security-conscious Linux users who want to ensure their networks are secure.
Version 1.4.6: N/A